How we cite our quotes: (Chapter.Paragraph)
Quote #7
"Good: I'm glad to see that you've been into the problem thoroughly, and aren't treating it like some stunt you can back out of if you don't like the way it's going. It's your life you're playing with, but I'd hate to feel I was helping you to commit suicide." (12.27)
Sullivan is a scientist, but he's no Frankenstein, throwing morality to the wind to delve deeper into the mysteries of life and the universe. Instead, he's interested in furthering science but not at the expense of his moral core. Sending Jan to his death would be totally against said moral core.
Quote #8
"Everybody on this island has one ambition, which may be summed up very simply. It is to do something, however small it may be, better than anyone else. Of course, it's an ideal we don't all achieve. But in this modern world the great thing is to have an ideal. Achieving it is considerably less important." (17.29)
The morality of Athens is to further a discipline—theater, painting, literature, and so on—by having an ideal. You've got to give them credit: That's a pretty unique way to answer the ethics question.
Quote #9
"I must take [the children] away and isolate them, for their protection, and for yours. Tomorrow my ships will begin the evacuation. I shall not blame you if you try to interfere, but it will be useless." (20.25)
Karellen's morality, like Karellen himself, is pretty foreign to what we consider morality. Taking children away from their parents is pretty hardcore and unmoral for people, but Karellen sees it as the only possible action. Again we wonder whether morality even applies to aliens.